Dab tsi yog lub luag haujlwm ntawm blackbody hauv infrared ntsuas kub
(1) Ib yam khoom uas nqus cov hluav taws xob sab nraud ntawm txhua lub wavelength yam tsis muaj kev xav hauv ib qho xwm txheej.
(2) Ib yam khoom uas muaj qhov nqus nqus ntawm 1
(3) Ib yam khoom uas nqus tag nrho cov hluav taws xob ntawm txhua qhov teeb meem wavelength ntawm qhov kub thiab txias. Txhua yam khoom muaj peev xwm ua kom tsis tu ncua radiate, nqus, thiab emit electromagnetic tsis. Cov hluav taws xob hluav taws xob hluav taws xob sib txawv sib txawv hauv ntau pawg, uas txhais tau tias lawv muaj qee qhov kev faib tawm spectral. Qhov kev faib tawm spectral no muaj feem xyuam rau cov yam ntxwv ntawm cov khoom nws tus kheej thiab nws qhov kub thiab txias, yog li nws hu ua thermal tawg. Yuav kom kawm txog kev cai lij choj hluav taws xob hluav taws xob uas tsis nyob ntawm qhov tshwj xeeb ntawm lub cev ntawm cov teeb meem, physicists tau txhais cov khoom zoo tshaj plaws - lub cev dub, raws li tus qauv khoom rau kev tshawb fawb hluav taws xob thermal. Lub npe hu ua blackbody yog hais txog qhov tseeb tias txhua qhov xwm txheej electromagnetic nthwv dej tau nqus, tsis muaj kev cuam tshuam los yog kis tau (qhov tseeb, lub cev dub tseem xav tau tawm sab nraud).
Kirchhoff txoj cai hluav taws xob hais tias qhov sib piv ntawm lub zog hluav taws xob los ntawm ib qho khoom hauv lub xeev thermal equilibrium rau nws tus nqi nqus tsis cuam tshuam rau lub cev ntawm cov khoom nws tus kheej, tab sis tsuas yog rau nws lub wavelength thiab kub. Raws li Kirchhoff txoj cai hluav taws xob, ntawm qhov kub thiab txias, lub cev dub yuav tsum yog ib qho khoom siv hluav taws xob loj, uas tuaj yeem hu ua lub tshuab hluav taws xob ua tiav. Cov electromagnetic nthwv dej tawm los ntawm cov khoom sib txawv hauv infrared thermal imaging yeej tsis cuam tshuam, thiab lub cev dub no tsuas yog siv cov khoom siv, sib npaug rau xoom point. Tab sis tsis muaj qhov zoo tshaj plaws blackbody nyob rau hauv lub ntiaj teb tiag tiag, yog li dab tsi yog siv los piav txog qhov txawv no? Rau txhua qhov wavelength, emissivity yog txhais raws li qhov piv ntawm lub zog hluav taws xob ntawm ib yam khoom tiag tiag rau lub zog hluav taws xob ntawm lub cev dub ntawm qhov kub thiab txias nyob rau hauv ib qho me me ntawm lub wavelength ntawm lub wavelength. Pom tseeb, qhov emissivity yog tus lej zoo ntawm 0 thiab 1, thiab feem ntau yog nyob ntawm cov khoom siv, ib puag ncig, thiab kev soj ntsuam. Yog hais tias lub emissivity yog ywj siab ntawm wavelength, cov khoom yuav hu ua lub cev grey, txwv tsis pub nws yog hu ua ib tug xaiv radiator.
Infrared thermal imagers tuaj yeem cuam tshuam los ntawm lwm yam hauv lub sijhawm siv mus ntev, ua rau muaj kev ua yuam kev, yog li kev ntsuas lub cev dub yog qhov tsim nyog.
